Man cooling overheated phone with fan

Do cases cause phones to overheat?

We´ve all been there, one minute your phone is a little warm to the touch and the next it resembles a blazing inferno!

Smartphones overheat with surprising regularity (Samsung famously had to recall its Galaxy Note 7 in 2016), but is it the case itself that´s turning your normally cool, collected smartphone into a hot-headed fire hazard?

In this article we´re going to explore the effects that phone cases have on overheating so that the next time your device starts to smolder, you´ll know whether or not to point the finger at your case!

Do phone cases cause phones to overheat (quick summary) – phone cases themselves don´t cause your phone to overheat, this is normally the result of prolonged usage or excessive exposure to sunlight. It is, though, recommended to take off your case if your phone gets REALLY hot, because it will probably be able to cool itself down more efficiently case-free. 

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Do phone cases cause overheating?

Phones overheat when their particles contain higher levels of kinetic energy than normal.

Basically, the longer we use our cell phone, the more collisions there are between electrons and positive ions (which is what creates kinetic energy).

The newest smartphones tend to overheat more because they´re so goddam jam-packed with power! According to the science buffs over at Cadence (world leaders in electronic design) – ´The more power you pack into a smartphone, the more those internals are going to heat up. ´

Put simply – power-packed device + long Candy Crush sessions = a hotter cell phone.

 

Ok, got you! So, it isn´t actually the phone case which is causing my iPhone to overheat?

Exactly! It´s the phone itself which is overheating!

Do phone cases ´trap´ heat?

Well, we first need to take a look at how phones cool themselves down.

It´s normally your phone´s inner-workings that really start to heat up! To counter this, ´heat spreaders´ are used to transfer the heat to the outer chassis of the phone. This is one of the reasons why the iPhone 11 is built with an aluminum frame; aluminum is an EXCELLENT conductor of heat!

It´s kind of like a chain, the heat is passed from one link to another until eventually there´s no heat left!

NOTE – we´ve seen some articles talking about BREATHABILITY and VENTS but this is NOT how smartphones dissipate heat!

Unlike computers, cell phones are too small (especially in today´s uber-competitive market) to be filled with fans, vents and other such cooling devices!

A phone case is going to cover your phone´s outer frame so it would be logical to assume that it ´traps´ the heat, right?

Well, it all depends on the type of case you´re using and the material that it´s made from. Let´s take a closer look –

The ´ClimateCase´

If, for whatever reason, you find that your phone is overheating a little too often, there are cases on the market that will actually cool your phone down!

The ´ClimateCase´ is more like a ´pouch´ than a traditional case but it enables your device to withstand both extreme heat AND cold! They´re also able to cool an already overheated phone in under 60 SECONDS (sounds like we should all be putting one of these in our desert survival kits!).

Special phone case which stops phones from overheating
Credit: ClimateCase

Aluminum (and other metals)

So, you´ve treated yourself to a heavy-duty aluminum case and you´re feeling pretty chuffed because you won´t be making that trip to the screen repair guy anytime soon!

But, wait, isn´t your phone going to get really hot?

Actually, no! Despite the size and bulkiness of your new case, the aluminum should act as a conductor and help your phone rid itself of that unwanted heat!

Here´s what the experts at Azo (the leading online publication for the Materials Science Community) have to say – ´Aluminum is an excellent heat conductor … [it is used] for many applications that need heat to be drained away rapidly, such as in computer motherboards´.

Sounds pretty convincing to us!

TPU / Polycarbonate / Silicone

Most cases on the market today are made from either TPU (a material similar to both rubber and plastic), polycarbonate (a ´firmer´ type of plastic) or silicone. 

So, do these materials allow heat to escape or do they have the opposite effect and ´trap´ the heat? 

Well, both TPU and silicone are poor conductors of heat which means that they may well interfere with the way in which your phone cools itself down.

As a general rule, if your smartphone feels REALLYYY hot, it´s probably a good idea to take a TPU / polycarbonate / silicone case off, because at least we know for sure that both Apple and Android devices are pretty good at cooling themselves down. A phone case on the other hand, well, it´s unlikely to aid the cooling process! 

Leather / Wood / ´Heavy´ fabrics (not that common, but, hey!)

They may look amazing, but leather, wood and fabrics such as wool are insulators, which means they´re good at keeping heat IN! If you´ve ever worn a leather jacket in hot weather WITHOUT a t-shirt, you´ll know exactly what I mean!

Again, it´s advisable to take your case off and let your phone do the heavy lifting!

Random plastic or metal cases from AliExpress, Wish, etc.

Since you can´t really be sure exactly what these cases are made from (even if ´100% aluminum, super-efficient thermal conductor´ is written in the product description), I´d definitely be a bit cautious! 

Conclusion

All being said and done, you needn´t be overly concerned!

A popular YouTuber recently carried out an ´experiment´ in which he repeatedly overheated a smartphone while wrapped in various different cases, including a metal case which quite literally covers the entire phone and a simple, bog-standard TPU case. The result?

Well, the phone was no warmer when using either type of case!

So, there you have it. There´s no need to be worried about a phone case CAUSING your phone to overheat!

Just remember, if your phone gets SUPER hot and you´re using a standard case (obviously not the ´ClimateCase´ which you just purchased for you next excursion into the Sahara), well, it´s probably better just to take it off!